Comparative Status of Fishes along the Course of the Pluvial White River, Nevada

Fish populations were sampled at 11 locations along the course of the pluvial White River, southeastern Nevada, in the 1960s and in 1983, and 3 sites in early 1984. The locations included Preston Big, Preston Town, and Lund Town springs, White River Valley, White Pine County; Moorman, Hot Creek, and Flag springs, White River Valley, Nye County; and Hiko, Crystal, and Ash springs, Pahranagat Valley, Lincoln County; and Moapa Valley Water District Spring and the Moapa River at Home Ranch, Moapa Valley, Clark County. Comparisons of species composition and abundance were made and, where possible, were related to historical data on settlement and habitat modifications. Negative impacts have accelerated during the past 20 years and the fishes in most of these sites have declined dramatically because of habitat alteration and reduction, and introductions of non-native species. One species became extinct before 1955, and our investigations show recent extirpations of taxa at two localities. Two taxa currently are listed as endangered. We submit rationale for endangered status for an additional seven taxa, threatened status for one, and special concern status for another. Only two fishes in this system presently remain comparatively safe.